A touch device, such as a mobile phone or a tablet PC, is more and more popular in our life. A capacitive touch device usually includes a number of touch sensors for detecting a touch operation applied on the touch device. However, in order to increase the resolution of the touch device, the number of touch sensors of the touch device become more and more, and then a response speed of the touch device is adversely affected. Thus, a touch device with increased response speed is needed.